1. Field of the Invention
The present invention relates to flat panel displays, such as field emission displays and plasma displays. Specifically, the present invention relates to an improved array of barriers for such flat panel displays and a method for making the same.
2. Description of Prior Art
Flat panel displays, such as a typical plasma display panel or a typical field emission display, are well known as display devices capable of replacing a cathode-ray tube (CRT) since they have a small volume, low power consumption, and are suitable for mass production. An array of barriers is used to support and insulate pixels in such flat panel displays. To achieve superior display features, barrier array should be made have a flat upper surface, and the height of the barrier array should be uniform throughout the entire barrier array. Furthermore, the material of which the barrier array is made should not be porous to prevent air from being trapped in the pores thereof. Thus the method for manufacturing barrier array is critical in making flat panel displays.
The two main methods for making barrier array in the art are the screen printing method and the sandblasting method. In the screen printing method, each barrier array is formed by repeatedly screen printing and drying paste material on a substrate, and then baking the assembly. However, during the repeated printing and drying procedure, it is difficult to ensure that the array has a flat upper surface and uniform height, and this leads to increases in production costs. In addition, it is also difficult to fabricate the barrier array with high precision when using the screen printing method. Thus, screen printing is not suitable for mass production of high quality barrier array.
A sandblasting method is also widely used, in which material for the barrier array is applied to a substrate at a predetermined thickness, and then dried. Then a protective film having the shape of the desired barrier array is formed on the assembly, or a sand blasting mask is attached to the assembly. Sand is injected at high pressure so that unwanted portions of the assembly are removed, thus forming the barrier array. Finally, the barrier array is baked. However, the whole manufacturing process takes a considerable time, and control of the sand injection must be highly accurate. The sandblasting method is not very reliable, and is also prone to contaminate the manufacturing environment with sand.
Other methods for making barrier array for flat panel displays use photolithography, molding, and casting. However, all these methods require mating of a substrate with suitable pastes, as well as drying and baking processes. This makes these methods unduly time-consuming. Furthermore, it is difficult to fabricate barrier arrays with high precision using these methods.